Well, I developed Freeciv Greatturn to try remedy the shortcomings of time constrains.
Greatturn is a multiplayer-only branch of Freeciv where matches are organized with about 20/30 players per map, and everybody takes only one turn per day, across a span of 2/3 months, until the match gets finished. With such big maps, there's a lot to do during each turn, and the positive improvement is that players can connect and make their moves at any time of the day, no matter of timezones or real-time synchronization.
What actually happens is that players who have little time to spend on Freeciv tend to organize their gameplay in a quick (more arcade?) approach, playing for about 10-15 minutes per day, while others with larger time allowances meditate deeper their strategy, form pokerface alliances and generally cooperate more tightly.
Right now we are playing on the continental America with 22 players.
In case you want to join the math, this is the link to Greatturn